AP Psychology Unit 1: Biological Basis of Behavior Flashcards

Vocabulary practice flashcards for AP Psychology Unit 1 covering heredity, nervous system subsystems, neural transmission, brain structures, sleep stages, and sensory mechanisms.

Heredity ("Nature")

Genetic or predisposed characteristics that influence physical, behavioral, and mental traits and processes.

Environmental Factors ("Nurture")

External factors that an individual experiences, such as family interactions or education.

Evolutionary Perspective

A psychological approach exploring how natural selection affects the expression of behavior and mental processes to increase survival and reproductive success.

Eugenics

The application of principles of the evolutionary perspective in ways that discriminate against others.

Central Nervous System (CNS)

The division of the nervous system consisting of the brain and spinal cord, interacting with all body processes.

Peripheral Nervous System (PNS)

The division of the nervous system that relays messages from the central nervous system to the rest of the body, divided into autonomic and somatic systems.

Autonomic Nervous System

A subsystem of the peripheral nervous system governing involuntary body processes; includes sympathetic and parasympathetic divisions.

Somatic Nervous System

A subsystem of the peripheral nervous system governing voluntary processes and skeletal muscle movements.

Sympathetic Nervous System

The division of the autonomic nervous system that prepares the body for action and fight-or-flight responses by increasing respiration and heart rate while decreasing digestion.

Parasympathetic Nervous System

The division of the autonomic nervous system that calms the body and returns it to a resting state by decreasing respiration and heart rate while increasing digestion.

Neurons

Neural cells that transmit information and form the structural basis of the nervous system.

Glial Cells

Cells in the nervous system that provide structure, insulation, communication, and waste transport for neurons.

Reflex Arc

A simple neural circuit in the spinal cord where sensory neurons, motor neurons, and interneurons work together to respond automatically to stimuli.

Sensory Neurons

Neurons that carry incoming sensory information from body tissues and sensory receptors to the central nervous system.

Motor Neurons

Neurons that carry outgoing instructions from the central nervous system to muscles and glands.

Interneurons

Neurons within the central nervous system that communicate internally and process information between sensory inputs and motor outputs.

Neuron Structure

Messages are received by dendrites, processed in the cell body (soma), transmitted along the axon, and sent via neurotransmitters released from terminal buttons across the synapse.

Action Potential

A brief electrical charge that travels down an axon when positive ions move inside the cell (depolarization).

Resting Potential

The electrical charge inside a non-firing neuron, maintained at approximately $-70\text{\textnormal{ millivolts}}$.

Depolarization

The movement of positive ions into the neuron during neural firing, making the internal electrical charge less negative.

All-or-Nothing Principle

The rule that a neuron fires completely or not at all once the stimulus reaches its threshold voltage.

Refractory Period

A short resting pause after a neuron has fired during which another action potential cannot be generated.

Reuptake

The reabsorption of excess neurotransmitters by the presynaptic terminal buttons after message transmission.

Acetylcholine (ACh)

A neurotransmitter responsible for muscle contractions, learning, and memory; deficiencies are associated with Alzheimer's disease.

Dopamine

A neurotransmitter associated with rewarding sensations; imbalances are linked to Parkinson's disease, schizophrenia, and drug addiction.

Endorphins

Neurotransmitters released during exercise that moderate pain and elevate mood.

Serotonin

A neurotransmitter involved in regulating sleep, mood, and eating; underactivity is associated with depression.

Norepinephrine

A neurotransmitter controlling arousal, learning, and mood regulation; underactivity is associated with depression.

GABA

The primary inhibitory neurotransmitter in the brain that lowers neural activity; imbalances are linked to anxiety disorders.

Glutamate

The primary excitatory neurotransmitter in the brain that makes an action potential more likely to occur.

Substance P

A pain enhancer that stimulates free nerve endings at the site of injury and increases pain messages within the spinal cord.

Adrenaline

A hormone secreted by the adrenal glands during stress or danger that increases blood circulation and respiration for fight-or-flight responses.

Leptin

A hormone that regulates hunger by signaling satiety (feeling full); sleep deprivation leads to lower leptin levels.

Ghrelin

The hunger hormone that increases the urge to eat; sleep deprivation leads to higher ghrelin levels.

Melatonin

A hormone secreted by the pineal gland in response to darkness that assists in timing the circadian rhythm.

Oxytocin

Known as the "cuddle hormone," it is secreted during physical affection like hugging and plays essential roles in childbirth and lactation.

Agonists

Psychoactive drugs that encourage or mimic neurotransmitter function to promote neural firing.

Antagonists

Psychoactive drugs that block or discourage neurotransmitter function to inhibit neural firing.

Reuptake Inhibitors

Psychoactive drugs that block the reabsorption of neurotransmitters back into the presynaptic neuron, leaving more in the synapse.

Stimulants

Psychoactive drugs (e.g., caffeine, cocaine) that increase neural activity.

Depressants

Psychoactive drugs (e.g., alcohol) that decrease neural activity.

Hallucinogens

Psychoactive drugs (e.g., marijuana) that cause distortions in perception and/or cognition.

Opioids

Psychoactive drugs (e.g., heroin) that act primarily as pain relievers.

Medulla

A brainstem structure controlling basic survival mechanisms such as breathing and heart rate.

Pons

A hindbrain structure involved in sleep, arousal, and left-right body movement coordination.

Cerebellum

A hindbrain structure controlling balance, muscle coordination, and forms of procedural/motor learning.

Reticular Activating System

A neural network in the brainstem that controls voluntary movement, eye movement, learning, cognition, emotion, and arousal.

Substantia Nigra

A midbrain structure involved in the initiation of voluntary motor activity.

Thalamus

A forebrain subcortical structure that routes incoming sensory information to the cortex for all senses except smell.

Hypothalamus

A forebrain subcortical structure regulating basic body functions (sleep, temperature) and drives (hunger, thirst, sex).

Hippocampus

A limbic system structure critical for the formation of new explicit memories.

Amygdala

A limbic system structure responsible for associating emotions with experiences.

Corpus Callosum

A thick band of neural fibers connecting the left and right cerebral hemispheres, severed in split-brain surgery to treat severe epilepsy.

Occipital Lobes

Cerebral cortex lobes located in the rear of the brain responsible for visual processing.

Temporal Lobes

Cerebral cortex lobes located on the sides of the head that control auditory processing, memory, and linguistic comprehension.

Parietal Lobes

Cerebral cortex lobes located near the top back of the head containing association areas and the somatosensory cortex for touch sensitivity and spatial information.

Frontal Lobes

Cerebral cortex lobes located behind the forehead responsible for executive functioning, higher-order thinking, planning, and voluntary muscle movement via the motor cortex.

Broca's Area

A region in the left frontal lobe responsible for speech production; damage causes Broca's aphasia.

Wernicke's Area

A region in the left temporal lobe responsible for speech comprehension; damage causes Wernicke's aphasia.

Brain Plasticity

The brain's ability to rewire itself, adapt, or create new neural connections throughout development to recover function after damage.

Circadian Rhythm

A biological internal clock operating on an approximate $24\text{\textnormal{-hour}}$ cycle that dictates sleep and wakefulness.

REM Sleep

Paradoxical sleep characterized by brain waves similar to wakefulness alongside muscle paralysis, rapid eye movement, vivid dreaming, and increased duration across the sleep cycle.

Activation-Synthesis Theory

A dream theory proposing that dreams are the brain's effort to synthesize and make sense of random neural activity occurring during sleep.

Absolute Threshold

The minimum intensity of physical energy needed to detect a stimulus at least $50\text{\textnormal{\%}}$ of the time.

Weber's Law

The principle that to perceive a difference between two stimuli, they must differ by a constant minimum percentage rather than a constant amount.

Synesthesia

A condition where sensory interaction causes one sensation channel to trigger an experience in another system (e.g., tasting colors).

Retina

The photosensitive inner surface at the back of the eye containing rods and cones that transduce light into neural messages.

Blind Spot

The point at which the optic nerve leaves the eye, creating a spot in the visual field where no photoreceptors exist.

Rods

Retinal photoreceptors located in the periphery that detect movement and shapes in low-light environments without processing color.

Cones

Retinal photoreceptors concentrated in the fovea that process visual detail and color (red, green, blue).

Opponent-Process Theory

The theory that color vision depends on opponent retinal ganglion cells (red/green, blue/yellow, black/white), which explains afterimages.

Prosopagnosia

A neurological condition resulting from damage to visual areas of the brain (occipital lobes) that leaves an individual unable to recognize faces.

Eye Anatomy

The visual pathway including the cornea, pupil, iris, lens, retina, optic nerve, optic chiasm, optic tract, thalamus visual area, and visual cortex.

Ear Anatomy

Structures of the auditory system including the pinna, external ear canal, eardrum, ossicles (malleus, incus, stapes), semicircular canals, and cochlea.

Cochlea

A spiral, fluid-filled cavity in the inner ear responsible for auditory transduction into nerve impulses in response to sound vibrations.

Semicircular Canals

Fluid-filled loops in the inner ear that detect head rotation and maintain the vestibular sense of balance.

Gustation

The chemical sense of taste, including sweet, sour, salty, bitter, umami, and oleogustus.

Gate Control Theory

The theory that the spinal cord contains a neurological gate that blocks pain signals or allows them to pass on to the brain.

Kinesthesis

The sensory system detecting body position and movement of individual body parts without relying on sight.

Vestibular Sense

The sensory system monitoring head position, balance, and orientation, regulated by semicircular canals in the inner ear.